This application relates to an ingredient suspension and an improved method of delivering ingredients to food products to provide aesthetic, nutrient, and product performance benefits to the food product, as well as an improved means of delivering such ingredients to food product units at very low levels with accuracy and consistency. In particular, this application relates to a process for preparing a flowable ingredient suspension and ingredient-fortified food products by applying the ingredient suspension onto the surface of the fihed or cooked pieces of the food.
A wide variety of starch and protein-based snack food products are presently available to the consumer. Many of these products are in the form of chips, strips, and extruded tubular pieces. Some of these products are expanded or puffed and contain a cellular or honeycombed internal structure. In addition, most of the present-day snack products contain a fairly high level of fat, either in the form of separately added ingredients, such as cheese, or in the form of fats imparted to the product during cooking, as in the case of corn or potato chips. Fat improves the flavor and palatability of these products. The use of nondigestible fats to replace the fat provides a lower calorie, good tasting snack.
Ingredient addition to snack products can be difficult due to a variety of product interactions, physical properties, environmental conditions, and process feasibility considerations. Often the situation is complicated by the high temperature of the application or the fact that there is a moving ingredient stream being applied to a moving product stream.
The nondigestible fat needs to be fortified with fat soluble vitamins to compensate for any loss of these vitamins by absorption into the nondigestible fats which are then excreted and not absorbed by the body. Vitamins, for example, have been applied to salted snacks as a powder, which can result in the loss of vitamin material. It can be difficult to obtain accurate and precise levels of addition applying vitamins to food products as a powder. The process is complicated by the relatively low amounts of material to be added, making flow control difficult. The powder composed of discrete particles can flow randomly with high variability easily influenced by environmental conditions. Adhesion to the food product can be low due to dissimilar surface tension or the governing physics of the application process that cause the particles to strike then repel away from the product surface.
Ingredient powders can be blended with salt, seasonings, or other particulate admixtures to act as carriers to improve metering capability. Segregation is a problem that increases the non-uniformity of the application and limits the maximum powder particle size to about 250 microns, preferably less than 150 microns. The lower particle size reduces, but does not eliminate segregation induced variability due to differences in total particle size distribution, bulk density, and particle shape between the vitamins and carrier. The salt or seasoning can preferentially adhere to the food product surface lowering the vitamin application rate further by competing for available space.
Addition with a salt or seasoning carrier has the disadvantage of coupling the vitamin addition control strategy with that of the carrier. The two materials can not be independently controlled which can lead to flavor or vitamin level problems. A further consideration with salt blends is that the salt will potentate undesirable vitamin flavors due to intimate contact during eating.
Many ingredients need to be added at extremely small levels that make accurate metering infeasible. Many flavors and nutrients are required in parts per million to parts per trillion levels.
The practice of over compensation, increasing the vitamin application rate or level in the carrier due to low adhesion, can leads to other undesirable effects, such as off-flavors. While over compensation can lead to higher average application levels, it also causes the upper tail of the ingredient level distribution to increase exponentially, in some cases double or triple the average level.
Many ingredients are sensitive to heat or oxygen exposure. Non-caloric sweeteners such as aspartame degrade upon heating. Application post heating is desirable to preserve ingredient quality. Oxidatively sensitive ingredients are difficult to maintain as powders since upon flow, intimate contact with air occurs. Providing these materials with a carrier with low oxygen solubility serving as a protective barrier provides a two fold advantage to improve metering capability and ingredient protection.
Imiscible liquids can be difficult to use. Separation will occur when added to low viscosity fluid systems. When used in powdered applications, undesirable wetting of the solid particulates can occur.
Environmental factors also govern the feasibility of applying many solid materials, particularly if they have the capability to act as humectants. Many seasoning applications contain reducing sugars or protein based materials that readily hydrate and form agglomerates which can prevent flow or create undesirable adhesion to process equipment.
Ingredients added for one purpose can have undesirable effects on other product quality attributes. Nutrients such as vitamins or minerals provide dietary benefits, but can provide off flavors. Vitamin A for example can provide undesirable flavors when added at recommended daily levels. Ideally, the ingredient carrier would provide some taste masking properties to allow higher levels to be used with less objectionable flavor properties. The addition of calcium carbonate to dough can create leavening and potential product texture problems upon heating. Addition post heating would eliminate uncontrolled product impacts.
Occupational health issues are a concern with the addition of some ingredients like protein based flavors, vitamins, or capcaisin which is used to make spicy foods by stimulating trigeminal nerves in the tongue. Airborne levels are typically strictly controlled to limit inhalation exposure.
PCT Patent Application US97/11400, filed Jul. 2, 1995 now WO 98/00038, published Jan. 8, 1998, discloses a method of fortifying food products with vitamins by applying to food products a suspension of vitamins in a flowable edible oil.
It is an object of this invention to provide an improved method of adding ingredients to food products, and particularly to fried snacks containing a nondigestible fat. It is a further object to provide a ingredient suspension containing an edible oil base and ingredients suspended therein, which is easily added to food products.
The present invention relates to a suspension of a food-additive ingredient in a flowable edible fat, the edible fat being a nondigestible fat, a digestible fat, or a mixture thereof. The suspension can be applied to warmed food products more evenly and efficiently than conventional powdered or liquid vitamins.
The present invention also relates to an improved method of adding food-additive ingredients to a food product, particularly a reduced fat fried snack product. The method comprises suspending the ingredients in a flowable edible fat, preferably a semi-solid nondigestible fat with reduced viscosity; optionally heating the ingredient suspension to a flowable temperature; and applying the ingredient suspension in a controlled amount to the surface of a food product. A preferred food product is a fabricated potato chip. The ingredient suspension is preferably applied when the chip is still hot, such as when just out of the fryer, oven or extruder.